Ah-hah! cgs! That at least explains the units, because according to wikipedia a Statcoulomb = erg^1/2 * cm^1/2. However it is still not entirely clear the motivation. I mean you can't just do something because the units work.

Staff: Mentor

I think that nasu is right. The electron is a quantum "point particle" meaning that it has no internal structure. The electron doesn't have a radius, per se, not in quantum mechanics and not classically either.

Easy Googling, folks! Compton radius is the name for what you get when equating rest mass with electrostatic energy.

But beware, you end up with superstition and fantasy in no time...
For all we know, electrons are pointlike. And yet they aren't obeying all the expected accompanying behaviour rules.
Can't find a reasonable quotation for the upper limit; thought it was around 10-30 m. Anyone know where to look ?

Easy Googling, folks! Compton radius is the name for what you get when equating rest mass with electrostatic energy.

But beware, you end up with superstition and fantasy in no time...
For all we know, electrons are pointlike. And yet they aren't obeying all the expected accompanying behaviour rules.
Can't find a reasonable quotation for the upper limit; thought it was around 10-30 m. Anyone know where to look ?

Thank You! That's exactly what it is. That explains it perfectly, although a strange concept this "Compton Radius". I wonder how useful it actually could be. It seems very incorrect to think of an electron in this way.